Devices and methods for cervix measurement

ABSTRACT

The present invention provides several devices and methods for determining dimensions of female reproductive organs. In one embodiment, a device for determining a dimension of a female reproductive organ includes a hollow member having a lumen, a measurement member insertable into the lumen of the hollow member and having a measurement scale disposed along a proximal portion, and a flange having a body offset substantially perpendicular to the hollow member. A device having a measurement member with a distal end extending substantially perpendicular to a main body, and an outer member with an open face and a space for advancement therethrough of the measurement member, wherein the outer member slidably engages the measurement member, is also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of application Ser. No. 09/877,986 entitled“Devices and Methods for Cervix Measurement,” filed on Jun. 8, 2001 nowU.S. Pat. No. 6,524,259.

FIELD OF THE INVENTION

The present invention relates to medical devices and methods of usingsuch devices. More particularly, the invention relates to instrumentsand methods to measure the length of the cervix in the fornix vaginaeand the dilation of the cervix uteri.

BACKGROUND

Preterm labor, or labor before 37 weeks gestation, has been reported in7 to 10 percent of all births but accounts for more than 85 percent ofall perinatal complications and death. Rush et al., BMJ 2:965-8 (1976)and Villar et al., Res. Clin. Forums 16:9-33 (1994), which are bothincorporated herein by reference. An inverse relationship betweencervical length in the fornix vaginae and the risk of preterm labor hasalso been observed. Anderson et al., Am. J. Obstet. Gynecol. 163:859(1990); Iams et al., N. Eng. J. Med. 334:567-72 (1996) and Heath et al.,and Ultrasound Obstet. Gynecol. 12:312-7 (1998), which all areincorporated herein by reference. Accordingly, many physicians find ituseful to examine the cervix in the fornix vaginae as part of normalprenatal care in order to assess risk of preterm labor.

It has long been known that the cervix normally undergoes a series ofphysical and biochemical changes during the course of pregnancy, whichenhance the ease and safety of the birthing process for the mother andbaby. For example, in the early stages of labor the tissues of thecervical canal soften and become more pliable, the cervix shortens(effaces), and the circumference of the proximal end of the cervicalcanal begins to increase at the internal os. As labor progresses, growthof the cervical diameter propagates to the distal end of the cervicalcanal, toward the external os. In the final stages of labor, theexternal os dilates allowing for the unobstructed passage of the fetus.

In addition to the physical and biochemical changes associated withnormal labor, genetic or environmental factors, such as medical illnessor infection, stress, malnutrition, chronic deprivation and certainchemicals or drugs can cause changes in the cervix. For example, it iswell known that the in utero exposure of some women todiethylstilbestrol (DES) results in cervical abnormalities and in somecases gross anatomical changes, which leads to an incompetent cervixwhere the cervix matures, softens and painlessly dilates withoutapparent uterine contractions. An incompetent cervix can also occurwhere there is a history of cervical injury, as in a previous traumaticdelivery, or as a result of induced abortion of the cervix is forciblydilated to large diameters. Details of the incompetent cervix arediscussed in Sonek, et al., Preterm Birth, Causes, Prevention andManagement, Second Edition, McGraw-Hill, Inc., (1993), Chapter 5, whichis incorporated by reference herein.

Cervical incompetence is a well-recognized clinical problem. Severalinvestigators have reported evidence of increased cervical os diameteras being consistent with cervical incompetence (see Brook et al., J.Obstet. Gynecol. 88:640 (1981); Michaels et al., Am. J. Obstet. Gynecol.154:537 (1986); Sarti et al., Radiology 130:417 (1979); and Vaalamo etal., Acta Obstet. Gynecol. Scan 62:19 (1983), all of which areincorporated by reference herein). Internal os diameters ranging between15 mm to 23 mm have been observed in connection with an incompetentcervix. Accordingly, a critical assessment in the diagnosis of anincompetent cervix involves measurement of the internal cervical osdiameter.

There are also devices and methods to measure the diameter of theexternal cervical os. For example, cervical diameter can be manuallyestimated by a practitioner's use of his or her digits. Although anindividual practitioner can achieve acceptable repeatability using thismethod, there is significant variation between practitioners due to thesubjective nature of the procedure. To address these concerns, variousmonitoring and measuring devices and methods have been developed. Forexample, an instrument for measuring dilation of the cervix uteri isdescribed in U.S. Pat. No. 5,658,295. However, this device is somewhatlarge, leading to a risk of injury to the findus of the vagina orcervical os. Additionally, it is not disposable and requires repeatedsterilization. Another device for measuring cervical diameter isdescribed, for example, in U.S. Pat. No. 6,039,701. In one version, thedevice described therein has a loop element that is secured to thecervix. The loop expands or contracts with the cervix and a gauge iscoupled to the loop for measuring changes in the loop dimension. Suchchanges can then be detected by electronic means. Accordingly, thisdevice is rather complex and expensive to manufacture.

Even if a woman is found to have an apparently normal internal cervicalos diameter, there may nonetheless be a risk for preterm labor anddelivery. Currently, risk assessment for preterm delivery remainsdifficult, particularly among women with no history of preterm birth.However, the findings that preterm delivery is more common among womenwith premature cervical shortening or effacement suggest that measuringthe length of the cervix would be predictive for preterm labor.

Currently, a physician has at least two options to measure the length ofthe cervix in the fornix vaginae. One such method involves serialdigital examination of the cervix by estimating the length from theexternal cervical os to the cervical-uterine junction, as palpatedthrough the vaginal fornix. Although this is useful for generalqualitative analysis, it does not afford an easy nor accuratemeasurement of the length of the cervix from the external cervical os tothe cervical-uterine junction (also described herein as the length ofthe cervix extending into the vagina) and, therefore, does not providean accurate assessment of the risk of preterm labor. Despite the use ofgloves, vaginal exams always carry with them the risk of transmittinginfectious agents, especially to the fetal membranes, the lining and/ormuscle of the uterus, or the fetus itself.

Another method involves real-time sonographic evaluation of the cervix.This method provides relatively quick and accurate cervical dimensions.However, it requires expensive equipment, highly skilled operators, aswell as skill in interpretation of results, which are all subject tohuman error. Also, due to the expense of the procedure many women,especially those without proper health insurance, cannot afford to havea sonographic test performed.

It would be beneficial if there were an instrument a practitioner coulduse to measure the cervix quickly and accurately, and with littlematerial expense. Although there are several instruments available fordetermining various dimensions of the uterus, there is no suitableinstrument for measuring the length of the cervix in the fornix vaginae.For example, U.S. Pat. No. 4,016,867 describes a uterine caliper anddepth gauge for taking a variety of uterine measurements, which althoughuseful for fitting an intrauterine contraceptive device, is not capableof measuring the length of the cervix in the fornix vaginae due tointerference by the caliper's wings. In fact, similar devices describedin U.S. Pat. Nos.: 4,224,951; 4,489,732; 4,685,747; and 5,658,295 sufferfrom similar problems due to their use of expandable wings or divergableprobe tips. These devices are also relatively sophisticated, making themexpensive to manufacture and purchase. U.S. Pat. No. 3,630,190 describesa flexible intrauterine probe, which is particularly adapted tomeasuring the distance between the cervical os and the fundus of theuterus. The stem portion of the device has a plurality of annular ridgesspaced apart from each other by a predetermined distance, preferably notmore than one-half inch apart. However, this device is not adapted foraccurately measuring the length of the cervix in the fornix vaginaebecause of the lack of an appropriate measuring scale and a stop forautomatically recording the measurement.

Accordingly, there is currently no commercially available, quick, andinexpensive as well as accurate device to assess the risk of pretermlabor by measuring the length of the cervix in the fornix vaginae.Therefore, many women at risk for preterm labor may be unaware of therisk to their pregnancy and their unborn child. If such a device wereavailable, many more women would be better informed about the course oftheir pregnancy and would then be able to make better choices aboutbecoming pregnant at all, or about managing their pregnancy to reducethe risk of preterm labor and injury to the unborn child.

Thus, there exists a need for a simple and inexpensive device that canbe used to determine the length of the cervix in the fornix vaginae and,thus, predict the risk of preterm labor, as well as other conditions.There is also a need for such a device that can measure the dilation ofthe cervix uteri, to provide an overall assessment of the cervix and todetermine the particular stage of labor. Ideally, the device should beadapted for use by a physician or obstetrician or even a trained nursein the doctor's office or clinic. Preferably, the device should bedisposable or capable of being sterilized. In addition, it is desirablethat device record the measurement automatically. The present inventionsatisfies these needs and provides related advantages as well.

SUMMARY OF THE INVENTION

The present invention provides devices and methods for determining adimension of a female reproductive organ.

In one aspect of the present invention, a device for determining adimension of an organ may include a hollow member with a distal end, aproximal end, and a lumen therebetween, and a measurement member with adistal portion, a proximal portion, and a measurement scale disposedalong the proximal portion, wherein the measurement member may beinserted into the lumen of the hollow member. The measurement scale ofthe measurement member may have a plurality of color-coded incrementalmarkings. Additionally, the device may include a flange having a bodyoffset substantially perpendicular to the hollow member, wherein theflange is attached to the distal end of the hollow member. A lightelement configured to emit light toward the distal end of themeasurement member may also be provided on the device.

The light element of the device may comprise a light emitting componentand an attachment means coupled to the light emitting component, whereinthe attachment means is configured to secure the light element to thehollow member. In one embodiment, the attachment means comprises screws.In another embodiment, the attachment means comprises snap-on clips.When equipped with a light element, the device may also include a powersource and a plurality of lead wires electrically coupling the lightemitting component of the light element to the power source. Inembodiments where the light element is disposed within the distalportion of the measurement member, the device may comprise a handlehaving an interior space, wherein the handle is attached to the proximalportion of the measurement member, a power source disposed within theinterior space of the handle, and a plurality of lead wires attached tothe power source and extending through the measurement member. In thisembodiment, the lead wires electrically couple the light element withthe power source.

The flange of the device may include a plurality of measurement markingson the body, and an opening suitable for advancement therethrough of themeasurement member. The flange may be constructed of a substantiallytranslucent material.

In another aspect of the present invention, a device for determining adimension of an organ is provided that includes a hollow member having adistal end, a proximal end, and a lumen therebetween, and a measurementmember having a distal portion, a proximal portion, and a measurementscale disposed along the proximal portion. The measurement member may beinserted into the lumen of the hollow member. The device may include aflange having a body offset substantially perpendicular from the hollowmember and an opening for advancement of the measurement membertherethrough. The flange may be attached to the distal end of the hollowmember.

The device may also incorporate a light element disposed within themeasurement member. In one embodiment, at least the distal portion ofthe measurement member is substantially translucent. The device mayinclude a handle attached to the proximal portion of the measurementmember and housing a power source, wherein the power source is coupledto the light element. Additionally, an outer sleeve may surround thehandle. The outer sleeve may comprise an outer shell with an interiorspace having a proximal region and a distal region, and a resilientelement within the proximal region of the interior space of the outershell, wherein the handle is disposed in the distal region of theinterior space of the outer shell.

In another aspect of the present invention, a device for determining adimension of an organ is provided that may include a measurement memberhaving a main body, a distal end extending substantially perpendicularto the main body, and a measurement scale along the member, and an outermember having a distal end, a proximal end, an open face, and a spacefor advancement therethrough of the measurement member. The outer memberslidably engages the measurement member. The outer member may include aplurality of extensions parallel to the open face. Here, the extensionssecure the measurement member within the space of the outer member. Inanother embodiment, the space of the outer member interlocks with themeasurement member to slidably engage the measurement member.

The distal end of the measurement member may be a tear-drop shape. Inanother embodiment, the distal end of the measurement member may be acircular shape. The measurement member may be angular in cross-section.When the measurement member is angular in cross-section, the space ofthe outer member may be angular in cross-section and configured toslidably engage the measurement member. Alternatively, the outer membermay be rectangular in cross-section.

Other objects and features of the present invention will become apparentfrom consideration of the following description taken in conjunctionwith the accompanying drawings.

DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a device of the present invention having ameasurement member, a hollow member, a flange, a locking mechanism, anda pin on the measurement member that travels within a slot on the hollowmember.

FIG. 2 illustrates a flange suitable for incorporation with the devicesof the present invention.

FIG. 3 illustrates a device as shown in FIG. 1 and further including adetachable light emitting component attached to the circumference of thehollow member.

FIG. 4 illustrates a device of the present invention that includes alight emitting component integrated into the measurement member andlocated in the distal portion of the measurement member, and a handlethat includes a power source for the light component.

FIG. 5 illustrates a device of the present invention having anotherembodiment of a locking mechanism.

FIG. 6a(i) is a cross-sectional view of a device of the presentinvention that includes a hollow member and a measurement member havingshapes configured for fixing the position of the measurement memberwithout the need for an additional locking mechanism.

FIG. 6a(ii) is a cross-sectional view of the device shown in FIG. 6a(i)showing a locked position of the hollow member and the measurementmember.

FIG. 6b is a cross-sectional view of a device of the present inventionincorporating a self-locking feature that includes a slot on the hollowmember and a protrusion on the measurement member designed to engage aside wall of the slot in order to fix the position of the measurementmember.

FIG. 6c is a cross-sectional view of a device of the present inventionincorporating a self-locking feature that includes an opening on thehollow member, a fastening member inserted into the opening, and a flatface on the measurement member, wherein the fastening member is insertedinto the opening and engages the flat face to fix the position of themeasurement member.

FIG. 6d is a cross-sectional view of a device of the present inventionincorporating a self-locking feature that includes a protrusion on theinner wall of the hollow member and a flat face on the measurementmember, wherein the protrusion engages the flat face to fix the positionof the measurement member.

FIG. 6e is a cross-sectional view of a device of the present inventionincorporating a self-locking feature that includes an opening on thehollow member, a fastening member, such as, e.g., a screw, inserted intothe opening, and an indentation extending longitudinally on themeasurement member, wherein the fastening member is inserted into theopening and engages the indentation to fix the position of themeasurement member.

FIG. 6f is a cross-sectional view of a device of the present inventionincorporating a self-locking feature that includes a protrusion on theinner wall of the hollow member and an indentation extendinglongitudinally on the measurement member, wherein the protrusion engagesthe indentation to fix the position of the measurement member.

FIG. 6g(i) is a cross-sectional view of a device of the presentinvention incorporating a self-locking feature that includes an openingon the hollow member, a fastening member inserted into the opening, andtwo flat faces on the measurement member.

FIG. 6g(ii) is a cross-sectional view of the device shown in FIG. 6g(ii)along the line 6 g(i).

FIG. 7 is a device of the present invention that includes a pressurecontrolling sleeve surrounding the handle of the device.

FIG. 8 is a top plan view of another device of the present invention.

FIG. 8A is a cross-sectional view of the device shown in FIG. 8 alongthe line 8A—8A.

FIG. 8B is a cross-sectional view of the device shown in FIG. 8 alongthe line 8B—8B.

FIG. 8C is a side view of the device shown in FIG. 8.

FIG. 8D is a side view of a measurement member of the device shown inFIG. 8.

FIG. 9 is a top plan view of another embodiment of a device of thepresent invention.

FIG. 9A is a cross-sectional view of the device of FIG. 9 along the line9A—9A.

FIG. 9B is a cross-sectional view of the device shown in FIG. 9 alongthe line 9B—9B.

FIG. 9C is a side view of the device shown in FIG. 9.

FIG. 9D is a side view of a measurement member of the device shown inFIG. 9.

DETAILED DESCRIPTION

The present invention provides various devices and methods fordetermining dimensions of female reproductive organs. For example, thedevice is particularly adapted for determining the length of the cervixin the fornix vaginae, which, as described above, is related to the riskof preterm labor in an individual. The device is also suited fordetermining the dilation of the cervix uteri, for predicting the risk ofpreterm labor or the particular stage of delivery. It is, however,contemplated herein, and also understood by those skilled in the art,that the invention can be used not only for determining variousdimensions of female reproductive organs. For example, the invention isusable for determining the dimension of any body cavity or passagewaywhere such a device would be insertable, such as a vagina, uterus,mouth, throat, nasal cavity, ear channel, rectum, and also to any cavitycreated and opened by surgery, for example, during chest, abdominal orbrain surgery. The device is also preferably fabricated from relativelyinexpensive materials and the measurement is quick to perform. Thus itallows the practitioner to repeat the test over time and therefore tomore closely monitor a woman's pregnancy and risk for preterm labor. Itis also contemplated that the device records the various measurementsautomatically, where the only input required by the practitioner is theproper insertion of the device into the body cavity or passageway. Thisis accomplished by the use of the flange to stop progression of thehollow member of the device while still allowing the measurement memberto be advanced within the body.

As used herein the term “distal” refers to the end or portion of adevice of the present invention, or a component thereof, that is adaptedto be inserted first into a body cavity or passageway. As such, it willbe that part of a device of the present invention furthest from the userwhile the device is inserted and progressed within the body cavity.Conversely, as used herein, the term “proximal” refers to the end orportion of the device nearest the user while the device is beinginserted and progressed within the body cavity.

Turning to FIG. 1, a measuring device 100 of the present invention isillustrated. Measuring device 100 includes an elongated hollow member104 having a distal region with a distal end, a proximal region with aproximal end, and a lumen extending between the distal and proximalends. An elongated measurement member 102 is provided and is designed tobe inserted into the hollow member 104, and specifically into the lumenof the hollow member 104. The measurement member 102 is elongate inshape and has a proximal region with a proximal end and a distal regionwith a distal end. The measurement member 102 is capable of beingprogressed coaxially within hollow member 104 both proximally anddistally. In the illustrated embodiment of measuring device 100,attached to the proximal end of the measurement member 102 is a handle112. In one embodiment, the handle 112 is molded from the same materialas the measurement member 102. Suitable materials and methods for themanufacture of the devices of the present invention are discussedherein. Alternatively, the handle 112 is a rubber or foam component thatis fitted on to and over the proximal end of the measurement member 102.

A measurement scale 118 is disposed along the proximal portion of themeasurement member 102. As used herein, the “measurement scale” refersto any number of a series of visual markings on the measurement member102 at or near the proximal end, which relate a measurement or distance.In a particularly preferred embodiment, the measuring scale 118 includesa plurality of millimeter (mm) incremental markings and a plurality ofcentimeter (cm) incremental markings. As illustrated in FIG. 1, themeasurement scale 118 includes relatively larger markings at 1, 2, 3, 4,and 5 cm in addition to a plurality of millimeter incremental markingsbetween the centimeter markings. Further, a critical mark 120 ispreferably present at approximately 2.5 cm. In one embodiment, thecritical mark 120 is presented in a different color, such as, e.g., ared color, relative to the other incremental markings of the measurementscale 118. The critical mark 120 is used to quickly notify a user ofdevice 100 that a particular cervix length represents a greater risk ofpreterm delivery relative to longer cervix lengths. In anotherembodiment of the device 100, the measurement scale 118 is coded into aplurality of regions. For example, in one implementation of thisembodiment, the incremental markings less than 2 cm are coded in a firstcolor, such as, e.g., red, the incremental markings from 2 to 3 cm arecoded in a second color, such as, e.g., yellow, and the incrementalmarkings from 3 to 5 cm are coded in a third color, such as, e.g.,green. In this embodiment, the measurement scale 118 is color-coded intothree regions that each visually represents the relative risks ofpreterm delivery for a cervix length falling within the respectiveregion. In the above described example, for instance, the red zoneindicates a shorter cervix, and therefore a higher risk of pretermdelivery, than the yellow zone, which indicates a cervix length thatreflects a higher risk of preterm delivery than the green zone. Themeasurement scale 118 is capable of being coded into regions based uponother distinguishing marks also, such as, e.g., a first region having afirst type of marking for the measurement increments, a second regionhaving a second type of marking for the measurement increments, and athird region having a third type of marking for the measurementincrements. In other embodiments of device 100, the incremental markingsare in English measurements, such as inches and increments thereof,rather than the metric increments previously discussed.

As illustrated, the device 100 preferably includes a slot 114 orientedalong the length-wise axis of hollow member 104. Additionally,measurement member 102 includes a pin 116 disposed distally from themeasurement scale 118. In operation, measurement member 102 is placedwithin hollow member 104 such that pin 116 protrudes through slot 114.As a result, measurement member 102 is slidable within hollow member 104while the rotation of measurement member 102 within hollow member 104 issignificantly reduced.

In another embodiment of device 100 designed to reduce the amount ofrotation of measurement member 102 while progressed within hollow member104, the measurement member 102 and hollow member 104 are not circularin shape. For example, both the measurement member 102 and hollow member104 may be rectangular, octagonal, square, or another shape having atleast one angle such that any rotation of the measurement member 102within hollow member 104 is substantially reduced and prevented by theangles of the measurement member 102 and hollow member 104. Anon-circular measurement member 102 and hollow member 104 mayadditionally include slot 114 on the hollow member 104 and pin 116 onthe measurement member 102 to further decrease the amount of rotationbetween the two members.

Attached to the distal end of hollow member 104 is a flange 106 that isshaped for non-abrasive contact with tissue. As seen in FIG. 1 and FIG.2, which is an illustration of device 100 along the line 2—2, the flange106 is preferably flat and spherically or conically shaped.Alternatively, however, the flange 106 may be any other non-abrasiveshape to reduce irritation and scraping of the cervical canal, fundus ofthe vagina or perforation of the findus of the uterus. The main body offlange 106 is also preferably offset from the longitudinal axis ofdevice 100. Additionally, flange 106 includes an opening 105 throughwhich measurement member 102 may be advanced distally after the flange106 contacts a bodily surface. When the device 100 is used to measurethe length of a cervix, the device 100 is advanced into the vagina untilflange 106 is placed into contact with the end of the cervix at theexternal uterine opening. At this point, further forward progress of thehollow member 104 within the cervical canal or further within the bodyis prevented as a result of the contact between flange 106 and the endof the cervix at the external uterine opening. Since flange 106 ispreferably offset from the longitudinal axis of device 100, in onemanner of operation optimal for measuring the length of the cervix,flange 106 is placed both in contact with the end of the cervix and alsocovering the external uterine opening. As a result, device 100 isoriented so that measurement member 102 is still able to be progressedwithin the fornix, rather than being advanced through the uterus, sincethe body of flange 106 is, with this method, covering the externaluterine opening. Subsequently, measurement member 102 is continued to beadvanced through opening 105 of flange 106 until the distal end of themeasurement member 102 contacts a wall of the body, such as, e.g., theanterior fornix. The length of the cervix is then measured by observingthe position of the proximal end of the hollow member 104 along themeasurement scale 118 of the measurement member 102.

In another embodiment of the device 100, the flange 106 further includesa plurality of measurement marks 122 that are, for example, usable formeasuring the dilation of the cervix or external uterine opening. Here,the flange 106 is preferably manufactured from a substantiallytransparent or translucent material, such as plastic, so that the useris able to observe the flange 106 while the flange 106 is placed withinthe body. After the flange 106 contacts the external uterine opening,the user is able to measure the dilation of the cervix by comparing thesize of the external uterine opening with the measurement marks 122 onthe flange 106. The measurement marks 122 may be metric, such as, e.g.,incremental marks of millimeters, centimeters, or a combination thereof,or in English scale, such as, e.g., inches.

Preferably, the flange 106 is secured to the distal end of the hollowmember 104 using a suitable attachment means, such as, e.g., anadhesive. Alternatively, the flange 106 may be formed as an integralcomponent of the hollow member 104.

Referring back to FIG. 1, a locking mechanism 124 is preferably locatedon the device 100 that allows a user to secure the measurement member102 within the hollow member 104 after a measurement of a body part,such as, e.g., the length of the cervix, has been taken. The lockingmechanism 124 preferably includes a collar 108 disposed around thecircumference of the hollow member 104 and a locking knob 110 insertableinto the collar 108. In one embodiment, as shown in FIG. 1, the lockingknob 110 resembles a fastening member, such as, e.g., a screw, with anenlarged area to facilitate the handling of the locking knob 110.Preferably, the locking knob 110 is ergonomically designed so that itmay also be used as a handle during the operation and positioning of thedevice 100 within the body. The collar 108 preferably includes anopening through which the locking knob 110 is capable of being inserted.Additionally, in this embodiment, the hollow member 104 also includes anopening through which the locking knob 110 is inserted after the lockingknob 110 is inserted into the collar 108. For example, after ameasurement of a body part is taken with the device 100, a user may lockthe position of the measurement member 102 within the hollow member 104,and therefore the position of the proximal end of the hollow member 104along the measurement scale 118 of the measurement member 102, byensuring that the openings of the collar 108 and the hollow member 104are aligned and then inserting the locking knob 110 through bothopenings simultaneously. The locking knob 110 is then threaded throughthe collar 108 and the hollow member 104 until the locking knob 110engages the measurement member 102. Once the locking knob 110 engagesthe measurement member 102, the locking knob 110 is tightened so thatmovement of the measurement member 102 proximally or distally within thehollow member 104 is prevented. In another embodiment, rather thanhaving an opening on the hollow member 104 for the locking knob 110, thehollow member 104 includes a deformable region around the circumferenceof the hollow member 104 at the approximate region where the lockingmechanism 124 is placed. Here, continued tightening of the locking knob110 compresses the deformable region of the hollow member 104, therebyplacing pressure against the measurement member 102 at the approximatepoint of the deformable region. Once the deformable region of the hollowmember 104 is sufficiently compressed by the locking knob 110, themeasurement member 102 is fixed in place within the hollow member 104.In one embodiment, the deformable region is formed by forming aplurality of slits along the circumference of the hollow member 104 atthe approximate location of the deformable region.

Turning to FIG. 3, a device 100 of the present invention is shown thatincludes a light component 126 secured to the hollow member 104. Thelight component 126 is capable of being oriented to direct light towardthe distal end of the hollow member 104. In operation, the lightcomponent 126 provides illumination within the body in order tofacilitate the placement of the device 100 within the body. Also, inembodiments of the device 100 where the flange 106 includes a pluralityof measurement marks 122, the light component 126 is capable of beingoriented to also direct light toward the flange 106, thereby increasingthe visibility of the measurement marks 122 on the flange 106 when thedevice 100 is within the body. As illustrated, the light component 126includes attachment means 128 used to secure the light component 126 tothe hollow member 104. In one embodiment, the attachment means 128 areremovable from the hollow member 104. The attachment means 128 may be,for example screws designed for secure insertion into correspondingopenings on the hollow member 104, or snap-on clips. When the lightcomponent 126 uses snap-on clips as the attachment means 128, the lightcomponent 126 may be positioned at various locations along the length ofthe hollow member 104 and at various positions around the circumferenceof the hollow member 104. In another embodiment, the light component 126is an integral part of the hollow member 104. Here, the light component126 is permanently affixed to the hollow member 104 in a predeterminedorientation, such as, e.g., an orientation that directs lightsubstantially toward the distal end of the hollow member 104 and toflange 106, and is not removable from the hollow member 104.

In one embodiment of light component 126, light component 126 is poweredusing a battery that is disposed within the interior of light component126. In another embodiment, an external power source is provided in lieuof a battery integrated into the interior of the light component 126.When an external power source is used, lead wires are provided thatelectrically couple the light component to the external power source.The lead wires preferably include a positive wire, a negative wire, anda ground wire. Alternatively, the lead wires include a positive wire anda negative wire, with one of the wires being grounded at some locationoutside the body, such as, e.g., near the external power source.

FIG. 4 is a device 200 of the present invention that incorporates alight element 230 as part of the measurement member 202. The device 200includes a hollow member 204 and a measurement member 202 configured toslide coaxially within the hollow member 204. Measurement member 202includes a measurement scale 218 on its proximal portion that issubstantially the same as measurement scale 118 of device 100.Similarly, device 200 includes a locking mechanism 224 that issubstantially the same as locking mechanism 124 of device 100. Forexample, as with locking mechanism 124, locking mechanism 224 preferablyincludes a collar 208 disposed around the circumference of the hollowmember 204 and a locking knob 210 insertable into the collar 208.Further, flange 206 of device 200 is substantially the same as flange106 of device 100 and is located at the distal end of hollow member 204.

Measurement member 202 of device 200 includes a lumen 216. Additionally,device 200 includes a light element 230 disposed within lumen 216. Asillustrated, the light element 230 is located in the lumen 216 in thedistal portion of the measurement member 202. In a preferred embodiment,the light element 230 is located at the distal end of the measurementmember 202. Light element 230 is a light-emitting component capable ofgenerating light that is directed substantially in a distal directionwhen the device 200 is placed within the body. Light element 230 may beany suitable light source, such as, e.g., a light-emitting diode, alaser, an incandescent light bulb, a fluorescent substance, or the like.In another embodiment, the light element 230 is an array of individuallight-emitting components rather than a single light-emitting component.When an array of individual light emitting components are used insteadof a single light emitting component, the light element 230 is capableof continually emitting light in the event one of the array of lightemitting components fails during the operation of device 200.

To allow for light to pass there through, measurement member 202 ispreferably manufactured of a substantially transparent or translucentmaterial such as plastic. In one embodiment, the entire measurementmember 202 is constructed from a substantially transparent ortranslucent material. In another embodiment, the distal portion of themeasurement member 202 is constructed from a substantially transparentor translucent material while the remaining portion of the member 202 isconstructed from a substantially opaque material such as a metallicsubstance.

A set of leads 232 a and 232 b electrically couple the light element 230to a power source 214. In a preferred embodiment, one of the leads is apositive electrical wire while the other lead is a negative electricalwire. In one embodiment, the leads 232 a, 232 b are disposed within thelumen 230 of the measurement member 202. The power source 214 is acomponent that is capable of providing power to the light element 230,such as, e.g., a battery or the like. As illustrated in FIG. 4, thepower source 214 is preferably located at the proximal end of themeasurement member 202 and, specifically, housed within a handle 212.The handle 212 is preferably positioned at the proximal end ofmeasurement member 202. The handle 212 has an internal space 222designed to house the power source 214. The internal space 222 ispreferably water tight to prevent damage to the power source 214, aswitch 216, or other components that may be disposed therein.

The handle 212 also includes a switch 216 electrically coupled to thepower source 214 that enables a user to control the power supplied tothe light element 230, as desired. In one embodiment, the switch 216enables a user to either turn on or turn off the supply of power to thelight element 230. Alternatively, the switch enables a user to vary theamount of power supplied to the light element 230, thereby allowing auser to variably dim the light element 230 rather than merely turning iton or off. In the illustrated embodiment, the switch 216 is a toggle orflip switch that may be alternated between a first position and a secondposition. The first and second positions generally correspond to on andoff positions respectively. In another embodiment, the switch 216 ispositioned at the proximal end of the handle 212, and is operated byturning the switch 216 in a circular fashion. Alternatively, the switch216 is a membrane component positioned at the proximal end of the handle212, and is operated by depressing the membrane.

In an alternative embodiment of device 200, measurement member 202 doesnot include a lumen 216 but, rather, is a solid member formed of atransparent or translucent material such as plastic. In this embodiment,the material that is used to form measurement member 202 encases bothlight element 230 and leads 232 a, 232 b. This is in comparison to theembodiment of device 200 illustrated in FIG. 4 wherein light element 230and leads 232 a and 232 b are positioned within a lumen 216. When thedevice 200 includes a solid measurement member 202 encasing lightelement 230 and leads 232 a, 232 b, movement of either light element 230or leads 232 a, 232 b within the member 202 is substantially restricted.This embodiment of measurement member 202 may be manufactured bycoextruding, from a plastic material, both measurement member 202 andleads 232 a, 232 b, thereby manufacturing a member 202 with built-inleads 232 a, 232 b. With the embodiment illustrated in FIG. 4, bycomparison, leads 232 a and 232 b lie freely within lumen 216.

In another embodiment of device 200, hollow member 204 is composed of asubstantially transparent or translucent material. When constructed ofsubstantially transparent or translucent material, hollow member 204enables light emitted from the light element 230 to also be emittedthere through. As a result, this embodiment of device 200 enables lightelement 230 to emit a greater percentage of light to the areassurrounding device 200.

Device 200, in another embodiment, includes a plurality of ports on thedistal portion of hollow member 204, such as ports 326 shown in FIG. 5and to be discussed herein. The ports allow an amount of light to beemitted through the hollow member 204 even when the hollow member 204 isnot constructed of a translucent material. For example, a hollow member204 manufactured from a metallic material or an opaque plastic materialwill still allow some amount of light to shine there through and ontothe areas surrounding the device 200 when hollow member 204 includes aplurality of ports on its distal portion.

Illustrated in FIG. 5 is a device 300 of the present invention. Device300 includes a hollow member 304 and a measurement member 302 configuredto slide coaxially within the hollow member 304. Flange 306, located atthe distal end of the hollow member 304, is substantially the same asflange 106 of device 100. Measurement member 302 is substantiallysimilar to measurement member 202 of device 300. For example,measurement member 302 includes a measurement scale 318 along itsproximal region.

Also, measurement member 302 includes a light element 330 disposed inthe distal portion of measurement member 302 and leads 332 a, 332 belectrically coupled to the light element 330. In a preferredembodiment, light element 330 is located at the distal end ofmeasurement member 302. Also, light element 330 is a light-emittingcomponent capable of generating light, such as, e.g., a light-emittingdiode, a laser, an incandescent light bulb, a fluorescent material, orthe like, and may be either a single light-emitting component or anarray of light-emitting components.

In one embodiment of measurement member 302, member 302 has a lumen 316in which light element 330 and leads 332 a, 332 b are disposed. Inanother embodiment, measurement member 302 has no lumen, but is solidand manufactured from a substantially transparent or translucentmaterial, such as, e.g., plastic. Here, measurement member 302 encaseslight element 330 and leads 332 a, 332 b, reducing the degree ofmovement of leads 332 a, 332 b, as compared to the measurement member302 having a lumen 316 and leads 332 a, 332 b lying freely within lumen316. For example, this embodiment of measurement member 302 may bemanufactured by being coextruded from a plastic material, and havingbuilt-in leads 332 a, 332 b.

The leads 332 a, 332 b are preferably a positive electrical wire and anegative electrical wire. Further, the leads 332 a, 332 b electricallycouple light element 330 to a power source 314, with may be, e.g., abattery or the like. As with device 200, the power source 314 of device300 is preferably located at the proximal end of the measurement member302 and, specifically, housed within a handle 312. The handle 312 ispreferably positioned at the proximal end of measurement member 302. Thepower source is housed within an internal space 322 of handle 312. Aswitch 316 on the handle 312 and electrically coupled to power source314 enables a user to turn on or off the power supplied to light element330. Alternatively, switch 316 allows a user to vary the level of powersupplied to light element 330 rather than merely providing an on or anoff setting.

Device 300 includes a locking mechanism 324 that includes a locking knob310 insertable into a collar 308. The collar 308 is disposed betweenfixed stops 328 a and 328 b. Fixed stop 328 a is located adjacent to thedistal end of collar 308, whereas fixed stop 328 b is located adjacentto the proximal end of collar 308. Fixed stops 328 a and 328 b maintaincollar 308 at a fixed position along the length of hollow member 304,i.e., the fixed stops 328 a and 328 b prevent the collar 308 from movingalong the length of hollow member 304. Although collar 308 is fixed inplace along the length of hollow member 304 by fixed stops 328 a, 328 b,the collar 308 is still rotatable around the circumference of hollowmember 304. As a result of the rotating aspect of collar 308,manipulation and operation of locking mechanism 324 is facilitated sincea user is able to rotate collar 308 to a suitable position whileoperating device 300. Other than the rotating aspect of lockingmechanism 324, locking mechanism 324 operates in substantially the samemanner as locking mechanism 124 of device 100. For example, in oneembodiment, hollow member 304 includes an opening that is configured forthe insertion of the locking knob 310 there through. Further, collar 308also includes an opening that is capable of being aligned with thatopening of the hollow member 304. Therefore, when a user desires to lockthe position of measurement member 302 within hollow member 304, theuser tightens locking knob 310, while knob 310 is inserted into collar308 and while the openings of collar 308 and hollow member 304 arealigned. The user continues tightening locking knob 310 until lockingknob 310 engages and contacts measurement member 302. As a result,locking knob 310 places pressure on measurement member 302, therebysubstantially preventing proximal or distal movement of the measurementmember 302 within hollow member 304. As with locking mechanism 124, ananother embodiment of locking mechanism 324 operates by compressing adeformable region on the hollow member 304 located substantially wherecollar 308 is placed on the circumference of the hollow member 304.Here, continued tightening of locking knob 310 exerts pressure on thedeformable region, thereby compressing that region and also placingpressure on measurement member 302.

As previously mentioned, device 300 includes a light element 330 that iseither disposed within a lumen 316 of measurement member 302 or encasedby measurement member 302 when member 302 does not include a lumen 316.The measurement member 302 is constructed, in whole or in part, of atransparent or translucent material in order to allow light emitted fromthe light element 330 to pass there through. In one embodiment, theentire measurement member 302 is constructed from a substantiallytransparent or translucent material. In another embodiment, the distalportion of the measurement member 302 is constructed from asubstantially transparent or translucent material while the remainingportion of the member 302 is constructed from a substantially opaquematerial such as a metallic substance.

In the illustrated embodiment, device 300 includes a plurality of ports326 located on the distal portion of hollow member 304. Ports 326 allowan amount of light to be emitted through hollow member 304 even whenhollow member 304 is manufactured from an opaque material, such as,e.g., a metallic substance. When hollow member 304 is manufactured froma metallic material or an opaque plastic material, light emitting fromlight element 330 will pass through both the measurement member 302, atthe transparent or translucent portions of member 302, and through ports326 of hollow member 304. As a result, ports 326 increase the areasurrounding device 300 that is illuminated by light element 330,particularly when hollow member 304 is composed of an opaque material.In an alternative embodiment, the entire body of hollow member 304 ismanufactured from a transparent or translucent material, therebyallowing light emitting from light element 330 to pass throughsubstantially the entire length of hollow member 304.

All of the devices of the present invention include alternativeembodiments where the position of the measurement member within thehollow member, after determining the length of the bodily part beingmeasured, is capable of being fixed without the use of lockingmechanisms 124, 224, or 324. Rather than requiring a separate lockingmechanism component 124, 224, or 324, these alternative embodiments ofthe devices of the present invention include hollow members andmeasurement members designed to self-lock, i.e., without requiring theseparate locking mechanisms of devices 100, 200, or 300. Several deviceshaving self-locking hollow members and measurement members areillustrated in cross-section in FIGS. 6a-f. The devices in FIGS. 6a-fincorporate hollow members and measurement members incorporatingself-locking features that, first, allow for the measurement member totravel longitudinally within the hollow member while also restrictingthe rotation of the measurement member within the hollow member. Second,the self-locking features of these devices allow for a user to fix theposition of the measurement member within the hollow member after ameasurement of a body part has been taken.

With the exception of the specifically discussed features, the devicesillustrated in FIGS. 6a-f are substantially similar to devices 100, 200,and 300. For example, the devices illustrated in FIGS. 6a-f all includean elongated measurement member insertable into an elongated hollowmember and capable of being advanced coaxially within the hollow member.A flange is present on the distal end of the hollow member and isoperable to stop the progression of the hollow member within a bodywhile enabling continued progression of the measurement member. Themeasurement member includes a measuring scale located on a proximalportion of the member, in addition to a handle attached to the proximalend of the measurement member. Further, the devices illustrated in FIGS.6a-f may incorporate any of the light emitting components discussedherein. Unlike devices 100, 200, and 300, however, the devices in FIGS.6a-d do not include a separate locking mechanism but, rather, includethe integrated self-locking features described herein.

Referring to FIGS. 6a(i) and 6 a(ii), one embodiment of a self-lockingdevice of the present invention, device 400(a), is illustrated. Aspreviously discussed, with the exception of a separate lockingmechanism, device 400(a) includes substantially the same components asthe other devices of the present invention, such as device 200 and 300,and is operated in substantially the same manner to obtain a measurementof a dimension of a body part. Device 400(a) includes a hollow member404(a) and a measurement member 402(a). Hollow member 404(a) andmeasurement member 402(a) are substantially similar to hollow member 104and measurement member 102, with the exception of the shapes of hollowmember 404(a) and measurement member 402(a). Hollow member 404(a) andmeasurement member 402(a) are oval in cross-section. Further,measurement member 402(a) is slightly flatter in cross-section thathollow member 404(a), i.e., has a shorter minor axis 419 than the minoraxis 421 of hollow member 404(a). As with the other embodiments of thedevices of the present invention, measurement member 402(a) is stillcapable of being placed within hollow member 404(a) and manipulatedcoaxially within hollow member 404(a). As seen in FIG. 6a(i), when auser desires to progress measurement member 402(a) within hollow member404(a), device 400(a) is operated so that measurement member 402(a) iscapable of being progressed coaxially within hollow member 404(a). Forexample, to enable to move measurement member 402(a) either distally orproximally within hollow member 404(a), device 400(a) is operated sothat the major axis 403 of measurement member 402(a) is substantiallyparallel to the major axis 405 of hollow member 404(a). When the majoraxes 403, 405 are substantially parallel, measurement member 402(a) maybe advanced within hollow member 404(a).

Due to the relative cross-sectional shapes of the members, however, theability to rotate measurement member 402(a) while traveling withinhollow member 404(a) is restricted. The restriction of the rotation ofmeasurement member 402(a) increases the ability to determine theposition of the proximal end of hollow member 404(a) along themeasurement scale of measurement member 402(a). Further, the position ofmeasurement member 402(a) within hollow member 404(a) is capable ofbeing fixed by forcibly rotating measurement member 402(a) while aportion of member 402(a) is still within hollow member 404(a). Forexample, to fix the position of measurement member 402(a) relative tohollow member 404(a), a user will forcibly rotate measurement member402(a) so that major axes 403, 405 are no longer in a parallelrelationship. As a result, measurement member 402(a) will come intocontact with the internal walls of hollow member 404(a) at at least twopoints along the internal walls of hollow member 404(a). The user thenproceeds to exert sufficient force to fix the position of measurementmember 402(a) within hollow member 404(a). Therefore, unlike devices100, 200, and 300, a separate locking mechanism is not required to fixthe position of measurement member 402(a) within hollow member 404(a).Alternative embodiments of device 400(a) are capable of utilizingdifferent cross-section shaped measurement members 402(a) and hollowmember 404(a) but having major axes 403, 405 that, when in substantialparallel relationship, enable measurement member 402(a) to bemanipulated within hollow member 404(a) and, when displaced from asubstantial parallel relationship, result in the fixation of measurementmember 402(a) within hollow member 404(a).

Referring to FIG. 6b, another embodiment of a self-locking device of thepresent invention, device 400(b), is illustrated. Device 400(b) includesa hollow member 404(b) having a slot 413 defined by side walls 413 a anda measurement member 402(b) having a protrusion 415. With the exceptionof a separate locking mechanism, device 400(b) includes substantiallythe same components as the other devices of the present invention, suchas device 200 and 300, and is operated in substantially the same mannerto obtain a measurement of a dimension of a body part. As with the otherdevices of the present invention, measurement member 402(b), duringoperation of device 400(b), is placed within, and in coaxial alignmentwith, hollow member 404(b) to allow measurement member 402(b) to bemanipulated proximally and distally within hollow member 404(b). Slot413, in a preferred embodiment, extends length wise, and forsubstantially the entire length, of hollow member 404(b). In anotherembodiment, slot 413 extends longitudinally along the distal portion ofhollow member 404(b) for at least a length that is substantiallyequivalent to the length of the measurement scale on the proximalportion of the measurement member 402(b). Protrusion 415 of measurementmember 402(b), in one embodiment, is a single protrusion located at oneposition on measurement member 402(b). In another embodiment, protrusion415 is a protrusion that extends length wise along substantially theentire length of measurement member 402(b). In the embodiment where slot413 extends longitudinally along the distal portion of hollow member404(b) for at least a length that is substantially equal to the lengthof the measurement scale, protrusion 415 is preferably a singleprotrusion located on the distal portion of measurement member 402(b).

While manipulating measurement member 402(b) within hollow member404(b), protrusion 415 is oriented so that it lies within slot 413. Thepositioning of protrusion 415 within slot 413 prevents undesiredrotation of measurement member 402(b) within hollow member 404(b) whilea body part is being measured. After measuring a bodily part usingmeasurement member 402(b), the position of member 402(b) within hollowmember 404(b) is capable of being fixed by rotating measurement member402(b) in order to forcibly engage protrusion 415 against a side wall413 a of slot 413. This is accomplished by, for example, continuing torotate measurement member 402(b) until protrusion 415 physicallycontacts a side wall 413 a and then continuing to apply rotationalpressure in that direction in order to force at least a portion ofprotrusion 415 beyond slot 413, i.e., at least a portion of protrusion415 is forced under a side wall 413 a. Consequently, the position ofmeasurement member 402(b) becomes fixed within hollow member 404(b)without requiring a separate locking mechanism.

FIG. 6c illustrates another embodiment of a self-locking device of thepresent invention, device 400(c). Device 400(c) includes a hollow member404(c) and a measurement member 402(c). Hollow member 404(c) includes anopening 417 through which a fastening member 407 may be inserted. Aswith the other fastening members of the other devices discussed herein,fastening member 407 may be, e.g., a screw. Measurement member 402(c)includes a flat face 409 that preferably extends the length of themember 402(c). In another embodiment, flat face 409 extendslongitudinally along the distal portion of measurement member 402(c) forat least a length that is substantially equivalent to the length of themeasurement scale on the proximal portion of the measurement member402(c). With this embodiment, the opening 417 and the fastening member407 are disposed on the distal portion of the hollow member 404(c).

Like the other devices of the present invention, measurement member402(c), during operation of device 400(c), is placed within, and incoaxial alignment with, hollow member 404(c). Measurement member 402(c)is then manipulated proximally or distally within hollow member 404(c)in order to determine the length of the body part being measured byobserving the location of the proximal end of hollow member 404(c) alonga measurement scale on the proximal portion of measurement member402(c). With the exception of a separate locking mechanism, device400(c) includes substantially the same components as the other devicesof the present invention, such as device 200 and 300, as is operated insubstantially the same manner to obtain a measurement of a dimension ofa body part.

During operation, fastening member 407 is inserted into opening 417 ofhollow member 404(c). While a measurement is being taken, the positionof fastening member 407 within opening 417 restricts the ability torotate measurement member 402(c) within hollow member 404(c). After ameasurement is taken, the position of measurement member 402(c) withinhollow member 404(c) is fixed by further tightening fastening member 407until it contacts the flat face 409 of measurement member 402(c). Tofacilitate this process, it may be necessary to orient measurementmember 402(c) in order for flat face 409 to align with opening 417 ofhollow member 404(c). Once fastening member 407 contacts the flat face409, additional tightening of fastening member 407 exerts pressure uponmeasurement member 402(c), thereby fixing measurement member 402(c) atthat position within hollow member 404(c). As a result, device 400(c)enables a user to fix the measurement member 402(c) at a given positionwithin hollow member 404(c) without requiring the use of a separatelocking mechanism, as compared to device 100, 200, and 300.

Referring now to FIG. 6d, another embodiment of a self-locking device ofthe present invention is shown. Device 400(d) includes a measurementmember 402(d) suitable for insertion within a hollow member 404(d). Likemeasurement member 402(c) of device 400(c), measurement member 402(d)includes a flat face 409 that preferably extends substantially thelength of the member 402(d). Hollow member 404(d) includes, on itsinternal surface, a ridge 411. In one embodiment, ridge 411 extendssubstantially the entire length of hollow member 404(d). In anotherembodiment, ridge 411 is a single dimple or protuberance at one locationon the internal surface of hollow member 404(d). In another embodimentof device 400(c), flat face 409 extends longitudinally along the distalportion of measurement member 402(d) for at least a length that issubstantially equivalent to the length of the measurement scale on theproximal portion of member 402(d). With this embodiment, ridge 411 is asingle protuberance disposed at one location on the internal surface ofthe distal portion of hollow member 404(d).

Device 400(c) includes substantially the same components as devices 200and 300, with the exception of the locking mechanisms of those devices,i.e., device 400(c) does not require a separate locking mechanism.Device 400(d) is also operated in substantially the same manner of theother devices of the present invention in order to determine a dimensionof a body part.

With device 400(d), however, measurement member 402(d), while adimension of a body part is being determined, is preferably orientedwithin hollow member 404(d) such that flat face 409 is oriented towardridge 411. In this manner, measurement member 402(d) is freely slidablecoaxially or longitudinally within hollow member 404(d). Additionally,the range of rotational movement of measurement member 402(d) withinhollow member 404(d) is limited by the combination of ridge 411 and flatface 409, i.e., ridge 411 restricts the rotation of measurement member402(d) when ridge 411 contacts an edge of flat face 409.

To fix the position of measurement member 402(d) within hollow member404(d), after determining the dimension of a body part, such as thelength of the cervix, the measurement member 402(d) is rotated so thatone edge of flat face 409 contacts ridge 411. Sufficient additionalrotational force is then applied to measurement member 402(d) so thatflat face 409, and therefore measurement member 402(d), is maintained ina fixed position by ridge 411. As a result, the incorporation of a ridge411 on the internal surface of hollow member 404(d) and a flat surface409 on measurement member 402(d) allows a user to fix the position ofmeasurement member 402(d) within hollow member 404(d), therebypreserving the location of the proximal end of hollow member 404(d)along a measuring scale on the proximal portion of measurement member402(d), i.e., a measurement of a dimension of a body part, without theuse of a separate locking mechanism.

Turning to FIG. 6e, another embodiment of a self-locking device of thepresent invention is shown. Device 400(e) includes a measurement member402(e) suitable for insertion within a hollow member 404(e). Measurementmember 402(e) includes an indentation 420 that extends longitudinallyalong the length of measurement member 402(e). Indentation 420preferably extends substantially the length of measurement member402(e). Hollow member 404(e) includes an opening 417 through which afastening member 407 may be inserted. Device 400(e) includessubstantially the same components as devices 200 and 300, with theexception of the locking mechanisms of those devices, i.e., device400(e) does not require a separate locking mechanism. Device 400(e) isalso operated in substantially the same manner of the other devices ofthe present invention in order to determine a dimension of a body part.

With device 400(e), however, measurement member 402(e), while adimension of a body part is being determined, is preferably orientedwithin hollow member 404(e) such that fastening member 407, which isinserted into opening 417 during operation, extends into indentation420. As a result, measurement member 402(e) is freely slidable coaxiallyor longitudinally within hollow member 404(e). Further, the range ofrotational movement of measurement member 402(e) within hollow member404(e) is limited by the extension of fastening member 407 withinindentation 420.

To fix the position of measurement member 402(e) within hollow member404(e), after determining the dimension of a body part, such as thelength of the cervix, fastening member 407 is tightened such that itengages the bottom surface of indentation 420. Subsequently, fasteningmember 407 is additionally tightened to ensure that measurement member402(e) is maintained in a fixed position by the engagement of the bottomsurface of indentation 420 by fastening member 407. As a result, theincorporation of an indentation 420 on measurement member 402(e), incombination with a fastening member 407 insertable into hollow member404(e) and capable of being engaged with indentation 420, allows a userto fix the position of measurement member 402(e) within hollow member404(e), thereby preserving the location of the proximal end of hollowmember 404(e) along a measuring scale on the proximal portion ofmeasurement member 402(e), i.e., a measurement of a dimension of a bodypart, without the use of a separate locking mechanism.

Referring now to FIG. 6f, another embodiment of a self-locking device ofthe present invention is shown. Device 400(f) includes a measurementmember 402(f) suitable for insertion within a hollow member 404(f). Likemeasurement member 402(e) of device 400(e), measurement member 402(f)includes an indentation 422 that preferably extends longitudinally alongsubstantially the length of the member 402(f). Hollow member 404(f)includes, on its internal surface, a protrusion 424. In one embodiment,protrusion 424 extends substantially the entire length of hollow member404(f). In another embodiment, protrusion 424 is a single dimple ordetent at one location on the internal surface of hollow member 404(f).Device 400(f) includes substantially the same components as devices 200and 300, with the exception of the locking mechanisms of those devices,i.e., device 400(f) does not require a separate locking mechanism.Device 400(f) is also operated in substantially the same manner of theother devices of the present invention in order to determine a dimensionof a body part.

With device 400(f), however, measurement member 402(f), while adimension of a body part is being determined, is preferably orientedwithin hollow member 404(f) such that protrusion 424 lies withinindentation 422. In this manner, measurement member 402(f) is freelyslidable coaxially or longitudinally within hollow member 404(f).Additionally, the range of rotational movement of measurement member402(f) within hollow member 404(f) is limited by the positioning ofprotrusion 424 within indentation 422.

To fix the position of measurement member 402(f) within hollow member404(f), after determining the dimension of a body part, such as thelength of the cervix, the measurement member 402(f) is rotated so thatone edge of indentation 422 contacts protrusion 424. Sufficientadditional rotational force is then applied to measurement member 402(f)so that indentation 422, and therefore measurement member 402(f), ismaintained in a fixed position by protrusion 424. As a result, theincorporation of a protrusion 424 on the internal surface of hollowmember 404(f) and an indentation on measurement member 402(f) allows auser to fix the position of measurement member 402(f) within hollowmember 404(f), thereby preserving the location of the proximal end ofhollow member 404(f) along a measuring scale on the proximal portion ofmeasurement member 402(f), i.e., a measurement of a dimension of a bodypart, without the use of a separate locking mechanism.

Turning to FIGS. 6(g)(i) and 6(g)(ii), another embodiment of aself-locking device of the present invention, device 500, is shown. FIG.6(g)(ii) is a cross-sectional view of device 500 along the line6(g)(ii). Device 500 includes a hollow member 504 and a measurementmember 502. A flange 506 is located at the distal end of hollow member504 and allows for measurement member 502 to slide there through. Hollowmember 504 includes an opening 517 through which a fastening member 507may be inserted. As with the other fastening members of the otherdevices discussed herein, fastening member 507 may be, e.g., a screw.Further, fastening member 507, in one embodiment of device 500, ispermanently fixed in position within opening 517 and hollow member 504.Measurement member 502 includes a first and second flat face 509 a, 509b that are in opposing relation to each other. The embodiment of device500 illustrated in FIG. 6g(i) includes flat faces 509 a, 509 b thatextend longitudinally along the distal portion of measurement member 502for at least a length that is substantially equivalent to the length ofa measurement scale 518 on the proximal portion of the measurementmember 502. Here, the opening 517 and the fastening member 507 aredisposed on the distal portion of the hollow member 504.

Like the other devices of the present invention, measurement member 502,during operation of device 500, is placed within, and in coaxialalignment with, hollow member 504. Measurement member 502 is thenmanipulated proximally or distally within hollow member 504 in order todetermine the length of the body part being measured by observing thelocation of the proximal end of hollow member 504 along a measurementscale on the proximal portion of measurement member 502. With theexception of a separate locking mechanism, device 500 includessubstantially the same components as the other devices of the presentinvention, such as device 200 and 300. In the embodiment of device 500shown in FIGS. 6(g)(i) and 6(g)(ii), the device 500 includes a handle512 attached to the proximal end of the measurement member 502 thathouses a power source 514 and a switch 516 that controls the applicationof power from the source 514 to a light element 530. The light element530 is preferably located within the distal portion of measurementmember 502 and is electrically coupled to the power source 514 via leadwires 532 a and 532 b. Lead wires 532 a and 532 b also electricallycouple the power source 514 to the switch 516. When a light element 530is provided, the measurement member 502 and the hollow member 504 aremanufactured from a substantially translucent material such as plastic.Alternatively, device 500 is provided without light element 530, powersource 514, switch 516, and lead wires 532 a, 532 b in order to reducemanufacturing costs of the device 500.

Device 500 is operated in substantially the same manner as, e.g.,devices 200 and 300 to obtain a measurement of a dimension of a bodypart. During operation, fastening member 507 is disposed within opening517 of hollow member 504. Preferably, measurement member 502 is orientedwithin hollow member 504 such that one of flat faces 509 a or 509 b ispositioned toward the fastening member 507. In one embodiment,corresponding markings are provided on the proximal portions of bothmeasurement member 502 and hollow member 504 that, when in alignment,indicate to the user that measurement member 502 is oriented such thatone of flat faces 509 a or 509 b is positioned toward fastening member507.

While a measurement is being taken, the position of fastening member 507within opening 517 restricts the ability to rotate measurement member502 within hollow member 504. For the embodiment of device 500 where thefastening member 507 is fixed in position within opening 517, after ameasurement is taken, the position of measurement member 502 withinhollow member 504 is fixed by forcibly rotating the measurement member502 until one of the ends 510, i.e., not flat face 509 a or 509 b, facesfastening member 507. When this is achieved, measurement member 502 isheld in place within hollow member 504 by pressure exerted by fasteningmember 507 on one of the ends of measurement member 502. Alternatively,in an embodiment of device 500 where fastening member 507 is notpermanently fixed but, rather, is removable from opening 517, to fix theposition of measurement member 502 a user may further tighten fasteningmember 507 until it contacts a flat face 509 a or 509 b of measurementmember 502. Once fastening member 507 contacts a flat face 509 a or 509b, additional tightening of fastening member 507 exerts pressure uponmeasurement member 502, thereby fixing measurement member 502 at thatposition within hollow member 504). As a result, device 500 enables auser to fix the measurement member 502 at a given position within hollowmember 504 without requiring the use of a separate locking mechanism, ascompared to devices 100, 200, and 300.

In another embodiment of the present invention, any of the devicesdisclosed herein is modified by the addition of a spring-loaded outersleeve 700 to the handle of that device. The spring-loaded outer sleeve700 of the present invention, when used in conjunction with one of thedevices disclosed herein, allows a constant pressure to be maintained onthe device, and specifically on the measurement member, while the deviceis being advanced within the body. The outer sleeve 700 also preventsundue pressure from being exerted against a bodily surface during theoperation of the device by absorbing some of the pressure used tomanipulate the device within the body. As a result, outer sleeve 700reduces the risk of the device puncturing a bodily wall while ameasurement of a dimension of a body part is taken with the device.

As illustrated in FIG. 7, outer sleeve 700 includes an outer shell 704capable of being placed over a handle of a device of the presentinvention. As shown in FIG. 7, outer sleeve 700, and specifically outershell 704, is placed over handle 212 of device 200. Outer sleeve 700 is,however, capable of being placed over any of the other handles of theother devices disclosed herein. Outer shell 704 includes sufficientinterior space to accommodate a handle of a device of the presentinvention as well as a spring element 702, or other resilient structure.In a preferred embodiment, spring element 702 is secured to a proximalwall of the outer shell 704 using a suitable attachment means, such as,e.g., an adhesive.

Preferably, outer shell 704 is placed over, for example, handle 212 ofdevice 200, and handle 212 is situated distally relative to springelement 702. A user will then advance measurement member 202 bymanipulating outer sleeve 700. As measurement member 202 is advanced,spring element 702 absorbs any force over a preset level, the levelbeing dependent on the resiliency of the spring element 702 incorporatedinto outer sleeve 700. Therefore, outer sleeve 700 prevents the forceused to advance measurement member 202 from exceeding a present level.Additionally, after the distal end of measurement member 202 contacts abody wall or surface, outer sleeve 700 prevents measurement member 202from puncturing that surface by absorbing additional force via springelement 702.

In one embodiment, outer sleeve 700 is manufactured from a metallicmaterial, such as, e.g., brass, stainless steel, or the like. In anotherembodiment, outer sleeve 700 is manufactured from a plastic material.When formed from plastic, outer sleeve 700 may be manufactured using aplastic extrusion technique known in the art. Preferably, the outersleeve 700 is placed on a handle of a device of the present invention,such as handle 212, at the time the entire device is manufactured andassembled. In one embodiment, the handle is placed into the outer shell704 and distal relative to the spring element 702. The distal end of theouter shell 704 is then crimped in order to fix the outer sleeve 700around the handle. In another embodiment, the handle is placed withinthe outer shell 704 and then a suitable element, such as, e.g., a washeror the like, is affixed over the distal opening of the outer shell 704using a suitable adhesive or soldering technique in order to maintainthe handle within the outer sleeve 700. Alternatively, the outer surfaceof the handle and the inner surface of the outer shell 704 of the sleeve700 may contain corresponding threads or grooves, thereby enabling thesleeve 700 to be threaded onto the handle. The outer sleeve 700, inanother embodiment, is press fit onto the handle.

Illustrated in FIG. 8 is another embodiment of the present invention,device 800. FIG. 8 is a top plan view of device 800, FIG. 8C is a sideview of device 800, and FIG. 8D is a side view of the measurement member802 of device 800 in isolation. Further, FIG. 8A is a cross-sectionalview of device 800 along the line 8A—8A shown in FIG. 8, and FIG. 8B isa cross-sectional view of device 800 along the line 8B—8B shown in FIG.8. Device 800 includes a measurement member 802 and an outer member 804.Measurement member 802 includes a measurement scale 818 that has aplurality of incremental markings. The incremental markings, in oneembodiment of device 800, extend for substantially the entire length ofmeasurement member 802. Outer member 804 includes an open side 805, seenin FIG. 8A, through which measurement member 802, and therefore themeasurement scale 818, is visible while the measurement member 802 isdisposed within the outer member 804. The open side 805 also includestwo extensions 807 that cover an edge of measurement member 802 whilemember 802 is disposed within outer member 804. Extensions 807 securemeasurement member 802 within outer member 804 while simultaneouslyallowing for movement of member 802 distally and proximally. Measurementmember 802 also includes a flange 806 located on its distal end. Theflange 806 is preferably a circular shape, a tear-drop shape, or anothershape that does not exhibit sharp angles.

In operation, measurement member 802 is placed within and is slidablyengaged by outer member 804. Measurement member 802 is capable of beingadvanced distally and proximally while engaged by outer member 804. Inone exemplary use of device 800, device 800 is used to measure thelength of the cervix. When used to do so, the device 800 is placedwithin the vagina and advanced distally until the distal end of outermember 804 comes into contact with the cervical-uterine junction. Then,the measurement member 802 is advanced distally until flange 806contacts the proximal surface of the cervix, thereby preventing furtherdistal movement of the measurement member 802. A user measures thelength of the cervix by observing the location of the measurement scale818 relative to the proximal end of the outer member 804.

In one embodiment, the position of the measurement member 802 relativeto the outer member 804 is maintained by friction between the members.For example, in this embodiment, measurement member 802 is manufacturedto fit snugly within outer member 804, but still allowing for movementdistally and proximally while engaged within outer member 804. The snugfit between the members enables the maintenance of the position ofmeasurement member 802 within outer member 804 after a measurement isrecorded.

FIG. 9 illustrates another embodiment of a device of the presentinvention, device 900. FIG. 9 is a top plan view of device 900, FIG. 9Cis a side view of device 900, and FIG. 9D is a side view of themeasurement member 902 of device 900 in isolation. FIG. 9A is across-sectional view of device 900 along the line 9A—9A shown in FIG. 9,and FIG. 9B is a cross-sectional view of device 900 along the line 9B—9Bshown in FIG. 9. Device 900 is similar to device 800 in that it includesa measurement member 902, having a measurement scale 918 with aplurality of incremental markings, and an outer member 904. Outer member904 includes an open side 905, seen in FIG. 9A, through whichmeasurement member 902 and measurement scale 918 is visible whilemeasurement member 902 is disposed within outer member 904. Measurementmember 902 also includes a flange 906 located on its distal end that ispreferably a circular shape, a tear-drop shape, or another shape thatdoes not exhibit sharp angles. Device 900 is also operable insubstantially the same manner as device 800.

Rather than the extensions 807 of device 800 that maintain measurementmember 802 within outer member 804, the outer member 904 of device 900interlocks with measurement member 902. As seen in FIGS. 9A and 9B,outer member 904 engages measurement member 902 without requiringextensions such as extensions 807 of device 800. Here, measurementmember 902 includes an angled body. Outer member 904 has angled space903 configured to accept measurement member 902. Due to the interlockingfit of outer member 904 and measurement member 902, measurement member902 is capable of being manipulated proximally and distally whiledisposed within angled space 903 of outer member 904. Also, theinterlocking fit of the members allows for measurement member 902 to beslidably engaged by outer member 904. During manufacture of device 900,outer member 904 may be crimped onto measurement member 902.

With regard to materials of manufacture, the devices of the presentinvention are capable of being formed from either metallic materials orplastic materials. In one embodiment, the devices are manufactured froma metal, such as, e.g., brass, stainless steel, aluminum, or the like,using techniques known in the art. When the devices of the presentinvention are formed of a metallic material, the devices are capable ofbeing sterilized in order to allow a device to be used repeatedly. Here,the devices are sterilized using an appropriate means, including, e.g.,chemical sterilization, thermal sterilization, radiation, and the like,after use in order to allow to extend the lifetime of the device. Inanother embodiment, the devices of the present invention are formed froma plastic material. With these embodiments, the devices may be extrudedfrom plastic using techniques known in the art. When plastic is used tomanufacture the devices, the devices are disposable. Consequently,contamination issues are avoided by virtue of producing devices that aredesigned to be disposed after use, as compared to the embodiments formedwith metal and requiring sterilization. The relative reduced cost ofutilizing plastics to manufacture the devices, as opposed to metals,allows for the plastic embodiments of the devices to be intended asdisposable units.

The present invention also provides various methods using the devices.For example, the invention provides a method for predicting the risk ofpreterm labor in an individual by performing the following steps. First,a device that includes a measurement member having a distal region and aproximal region, a hollow member through which the measurement member isinserted and advanced, and a flange engaged with the distal end of thehollow member, is inserted into the vagina. The flange of the device hasa surface adapted to contact the cervix at the external uterine openingafter the distal end of the hollow member is inserted into the vagina.The device is advanced within the vagina until the flange contacts thecervix at the external uterine opening. At this point, forward progressof the hollow member is prevented. The measurement member is continuedto be advanced until the distal region of the measurement membercontacts the cervical-uterine junction at the fornix vaginae.Subsequently, the length of the cervix in the fornix vaginae isdetermined by observing the position of the proximal end of the hollowmember along a measurement scale located on the proximal portion of themeasurement member. The length of the cervix in the fornix vaginae isinversely related to the risk of preterm labor.

As used herein the term “risk of preterm labor” refers to the risk thatan individual will enter labor before the thirty-seventh week ofgestation or pregnancy. Using the methods and devices of the presentinvention, in certain circumstances this risk can be predicted eitherwhen the individual is already pregnant or when the individual is notpregnant. When it is possible to evaluate the risk of preterm labor, apatient may gain valuable insight on what may occur during thepregnancy. Also as used herein the term “preterm delivery” is usedinterchangeably with preterm birth and refers to birth of the fetus asthe result of preterm labor. Accordingly, it is contemplated thatpreterm delivery would occur as the result of preterm labor. Becausebabies born prematurely may have serious health problems, practitionerstry to avoid preterm labor it at all possible. If vaginal bleedingoccurs or if the fetal membranes rupture, preterm labor is difficult tostop. If, however, vaginal bleeding does not occur, and the membranesare not leaking amniotic fluid, bed rest with fluid given intravenouslyhelps approximately one in two women. It should also be noted that ifthe cervix dilates beyond 5 centimeters, labor usually continues untilthe baby is born. Typically, magnesium sulfate given intravenously stopslabor in a majority of cases. Using the devices and methods of thepresent invention will indicate whether such treatment may be needed inthe future.

The invention also provides a method for predicting the risk ofmiscarriage in an individual. First, a device that includes ameasurement member having a distal region and a proximal region, ahollow member through which the measurement member is inserted andadvanced, and a flange engaged to the distal end of the hollow member,is inserted into the vagina. The flange of the device has a surfaceadapted to contact the cervix after the distal end of the hollow memberis inserted into the vagina. The device is advanced within the vaginauntil the flange contacts the cervix, preferably at the external uterineopening. At this point, forward progress of the hollow member isprevented. The measurement member is continued to be advanced until thedistal region of the measurement member contacts the cervical-uterinejunction at the fornix vaginae. Subsequently, the length of the cervixin the fornix vaginae is determined by observing the position of theproximal end of the hollow member along a measurement scale located onthe proximal portion of the measurement member. The length of the cervixin the fornix vaginae is inversely related to the risk of miscarriage.

The present invention also provides methods for predicting the ease ofinducing labor. First, a device that includes a measurement memberhaving a distal region and a proximal region, a hollow member throughwhich the measurement member is inserted and advanced, and a flangeengaged to the distal end of the hollow member, is inserted into thevagina. The flange of the device has a surface adapted to contact thecervix after the distal end of the hollow member is inserted into thevagina. The device is advanced within the vagina until the flangecontacts the cervix, preferably at the external uterine opening. At thispoint, forward progress of the hollow member is prevented. Themeasurement member is continued to be advanced until the distal regionof the measurement member contacts the cervical-uterine junction at thefornix vaginae. Subsequently, the length of the cervix in the fornixvaginae is determined by observing the position of the proximal end ofthe hollow member along a measurement scale located on the proximalportion of the measurement member. The length of the cervix in thefornix vaginae is inversely related to the ease of inducing labor.

The invention further provides a method for assessing the fertility ofan individual. First, a device that includes a measurement member havinga distal region and a proximal region, a hollow member through which themeasurement member is inserted and advanced, and a flange engaged to thedistal end of the hollow member, is inserted into the vagina. The flangeof the device has a surface adapted to contact the cervix after thedistal end of the hollow member is inserted into the vagina, includes ameasurement scale, and is substantially translucent. Also, the flange ispreferably off-set to the side of the hollow member to allow the flangeto cover the external uterine opening while also allowing for thefurther advancement of the measurement member toward the fornix. Thedevice is advanced within the vagina until the flange contacts thecervix, and preferably is placed against the external uterine opening.At this point, forward progress of the hollow member is prevented. Themeasurement member, however, is continued to be advanced toward thefornix until the distal region of the measurement member contacts thecervical-uterine junction at the fornix vaginae. Subsequently, thelength of the cervix in the fornix vaginae is determined by observingthe position of the proximal end of the hollow member along ameasurement scale located on the proximal portion of the measurementmember. Additionally, the dilation of the cervix is measured using themeasurement scale on the flange. The length of the cervix in the fornixvaginae is inversely related to the fertility of an individual.

As used herein, the term “fertility” refers to the ability of a femaleto carry a fetus to the point where it is viable or can survive with thehelp of medical science, if necessary, when delivered, a femaleattempting pregnancy, preconceptional evaluation, or procedures involvedwith infertility treatment. Accordingly, fertility generally refers tothe ability of a female to carry a fetus to a normal nine month term, aswell as to any other shorter term where the infant would survive on itsown or with critical care. By assessing the cervical length anddiameter, a practitioner may achieve an appreciation of the fertility ofthe female, because a risk for preterm labor can be predicted. Forexample, if the practitioner can determine that a female is at risk forpreterm labor and preterm delivery, and that the infant's chances forsurvival would be small, then the practitioner can advise the female ofthe risk. Accordingly, the female can make the decision to avoidpregnancy or can, with the assistance of her physician, take stepsthrough diet, rest, and medications to lessen the risk of preterm labor.

As used herein the term “female” refers to a mammalian female, such as ahuman, horse, dog, cow, pig or monkey. Although the devices and methodsare particularly adapted for use in a human female, one skilled in theart understands that they may be used in any female mammal. Accordingly,the devices and methods of the present invention could be used inveterinary medicine, if desired. When used in veterinary medicine, thedevices and methods are specifically adapted for the type of animal onwhich the devices and methods will be used. For example, a device of thepresent invention adapted for equine use will include a hollow memberand a measurement member that is greater in length relative to a deviceadapted for human use. The hollow member and the measurement member mustboth be of a sufficient length to enable a veterinarian to measure thelength of the cervix, the dilation of the cervix, and the depth of theuterus of a female horse. Since the equine vaginal canal is longer thana human vaginal canal, both the hollow member and the measurement memberof the devices of the present invention must accordingly be longer whenadapted for equine use.

EXAMPLE I Cervix Length Measurement

This example provides measurement of the length of the cervix in thevagina in a subject and correlation with reported criteria fordetermining the risk of preterm delivery.

The subject preferably lies in a prone position on her back. In oneprocedure, the practitioner uses a speculum to first examine the vaginalcavity and to observe the optimum position for placing the device. Thepractitioner then inserts into the vagina a device that includes ameasurement member having a distal region and a proximal region, ahollow member through which the measurement member is inserted andadvanced, and a flange engaged to the distal end of the hollow member.Alternatively, the practitioner may insert the device into the vaginawithout first using the speculum. The flange of the device has a surfaceadapted to contact the cervix at the external uterine opening after thedistal end of the hollow member is inserted into the vagina. Thepractitioner next advances the hollow member within the vagina until theflange contacts the cervix at the external uterine opening. At thispoint, forward progress of the hollow member is prevented. Thepractitioner then progresses the measurement member through the hollowmember until the distal region of the measurement member contacts thecervical-uterine junction at the fornix vaginae. Subsequently, thepractitioner determines the length of the cervix in the fornix vaginaeby observing the position of the proximal end of the hollow member alonga measurement scale located on the proximal portion of the measurementmember. Since the length of the cervix in the fornix vaginae isinversely related to the risk of preterm delivery, the practitioner isthen able to determine that risk in the patient. The practitioner usesthe data provided herein in Table 1, discussed in Iams et al., N. Eng.J. Med. 334:567 (1996); which is incorporated by reference herein, inorder to determine the relative risk of preterm delivery.

TABLE I Relative Risk of Preterm Delivery Length of cervix (mm)Percentile at 24 weeks at 28 weeks 40 ≦75 2 2.8 35 ≦50 2.4 3.5 30 ≦253.8 5.4 26 ≦10 6.2 9.6 22 ≦5 9.5 13.9 13 ≦1 14 24.9

As used herein, the term “relative risk” refers to the likelihood thatthere will be a preterm delivery when compared to the population thatdoes not have that finding. In this subject, the length of the cervix isdetermined to be 22 mm. Since the subject is at 24 weeks of gestation,the relative risk for preterm delivery for this subject is 9.5. In otherwords, this subject has a 9.5 higher risk for preterm delivery than anindividual whose cervix is greater than 22 mm in length.

EXAMPLE II Cervix Dilation Measurement

This example demonstrates the use of the invention disclosed herein tomeasure the dilation of the cervix uteri in the same subject as inExample 1, to predict the risk for preterm delivery or the particularstage of delivery in a normal pregnancy.

One of the devices of the present invention is used to measure thedilation of the cervix uteri. A physician inserts into the vagina adevice that includes a measurement member having a distal region and aproximal region, a hollow member through which the measurement member isinserted and advanced, and a flange engaged to the distal end of thehollow member. The flange of the device has a surface adapted to contactthe cervix after the distal end of the hollow member is inserted intothe vagina, includes a measurement scale, and is substantiallytranslucent. Also, the flange is preferably off-set to the side of thehollow member to allow the flange to cover the external uterine openingwhile also allowing for the further advancement of the measurementmember toward the fornix. The device is advanced within the vagina untilthe flange contacts the cervix at the external uterine opening. Thephysician then measures the dilation of the cervix by comparing thedilation of the cervix with the measurement scale on the flange. Usingthis procedure, the dilation of the cervix uteri is this subject isfound to be 5 cm. Accordingly, the physician advises the subject thatdelivery is imminent. Since this subject is in her 24^(th) week ofpregnancy, this delivery is premature or preterm.

Although the invention has been described with reference to the examplesprovided above, it should be understood that various modifications canbe made without departing from the spirit of the invention. Accordingly,the invention is limited only by the claims.

What is claimed is:
 1. A device for determining a dimension of an organcomprising: a hollow member having a distal end, a proximal end, and alumen therebetween, a measurement member having a distal portion, aproximal portion, and a measurement scale disposed along the proximalportion, wherein the measurement member is insertable into the lumen ofthe hollow member, a flange having a body offset substantiallyperpendicular to the hollow member, wherein the flange is attached tothe distal end of the hollow member, and a light element configured toemit light toward the distal end of the measurement member, the lightelement comprising a light emitting component and an attachment meanscoupled to the light emitting component, wherein the attachment means isconfigured to secure the light element to the hollow member and theattachment means comprises screws.
 2. The device of claim 1, furthercomprising a power source and a plurality of lead wires electricallycoupling the light emitting component of the light element to the powersource.
 3. The device of claim 1, wherein the flange comprises aplurality of measurement markings on the body, and an opening suitablefor advancement therethrough of the measurement member.
 4. The device ofclaim 3, wherein the flange is constructed of a substantiallytranslucent material.
 5. The device of claim 1, wherein the measurementscale of the measurement member comprises a plurality of color-codedincremental markings.
 6. A device for determining a dimension of anorgan comprising: a hollow member having a distal end, a proximal end,and a lumen therebetween, a measurement member having a distal portion,a proximal portion, and a measurement scale disposed along the proximalportion, wherein the measurement member is insertable into the lumen ofthe hollow member, a flange having a body offset substantiallyperpendicular to the hollow member, wherein the flange is attached tothe distal end of the hollow member, and a light element configured toemit light toward the distal end of the measurement member, the lightelement comprising a light emitting component and an attachment meanscoupled to the light emitting component, wherein the attachment means isconfigured to secure the light element to the hollow member and theattachment means comprises snap-on clips.
 7. The device of claim 6,further comprising a power source and a plurality of lead wireselectrically coupling the light emitting component of the light elementto the power source.
 8. The device of claim 6, wherein the flangecomprises a plurality of measurement markings on the body, and anopening suitable for advancement theretbrough of the measurement member.9. The device of claim 8, wherein the flange is constructed of asubstantially translucent material.
 10. The device of claim 6, whereinthe measurement scale of the measurement member comprises a plurality ofcolor-coded incremental markings.